Added DeleteGroupEvent and GroupDoesNotExistException

src/main/java/mops/gruppen2/controller/Gruppen2Controller.java

@@ -29,7 +29,8 @@ public class Gruppen2Controller {
         this.groupService = groupService;
     }
 
-    /**Zeigt die index.html an.
+    /**
+     * Zeigt die index.html an.
      *
      * @param token toller token
      * @param model tolles model

src/main/java/mops/gruppen2/domain/Aggregate.java

@@ -30,8 +30,7 @@ public abstract class Aggregate {
             Method method = this.getClass().getDeclaredMethod("applyEvent", event.getClass());
             method.setAccessible(true);
             method.invoke(this, event);
-        }
+        } catch (IllegalAccessException e) {
-        catch (IllegalAccessException e) {
             e.printStackTrace();
         } catch (NoSuchMethodException e) {
             e.printStackTrace();

src/main/java/mops/gruppen2/domain/Exceptions/GroupDoesNotExistException.java

@@ -0,0 +1,9 @@
+package mops.gruppen2.domain.Exceptions;
+
+import mops.gruppen2.domain.event.Event;
+
+public class GroupDoesNotExistException extends EventException {
+    public GroupDoesNotExistException(String msg) {
+        super(msg);
+    }
+}

src/main/java/mops/gruppen2/domain/Group.java

@@ -77,4 +77,8 @@ public class Group extends Aggregate {
             throw new UserNotFoundException("Nutzer wurde nicht gefunden!");
         }
     }
+
+    private void applyEvent(DeleteGroupEvent event) {
+        this.id = this.id * -1;
+    }
 }

src/main/java/mops/gruppen2/domain/event/DeleteGroupEvent.java

@@ -0,0 +1,13 @@
+package mops.gruppen2.domain.event;
+
+import lombok.EqualsAndHashCode;
+import lombok.Value;
+
+@EqualsAndHashCode(callSuper = true)
+@Value
+public class DeleteGroupEvent extends Event {
+
+    public DeleteGroupEvent(long event_id, long group_id, String user_id) {
+        super(event_id, group_id, user_id);
+    }
+}

src/main/java/mops/gruppen2/service/GroupService.java

@@ -1,8 +1,8 @@
 package mops.gruppen2.service;
 
 import mops.gruppen2.domain.Exceptions.EventException;
+import mops.gruppen2.domain.Exceptions.GroupDoesNotExistException;
 import mops.gruppen2.domain.Group;
-import mops.gruppen2.domain.event.AddUserEvent;
 import mops.gruppen2.domain.event.CreateGroupEvent;
 import mops.gruppen2.domain.event.Event;
 import org.springframework.stereotype.Service;
@@ -18,17 +18,32 @@ public class GroupService {
      * @param eventList Die restlichen Events für diese Gruppe
      * @return Gruppe auf aktuellem Stand
      */
-    Group buildGroupFromEvents(List<Event> eventList) {
+    Group buildGroupFromEvents(List<Event> eventList) throws EventException {
         Group newGroup = new Group();
 
         try {
+            if (!(eventList.get(0) instanceof CreateGroupEvent)) {
+                throw new GroupDoesNotExistException("Die Gruppe existiert nicht");
+            } else {
+                newGroup.applyEvent(eventList.get(0));
+                eventList.remove(0);
+            }
             for (Event event : eventList) {
+                if (!(newGroup.getId() > 0)) {
+                    throw new GroupDoesNotExistException("Die Gruppe existiert nicht");
+                }
                 newGroup.applyEvent(event);
             }
         } catch (EventException e) {
+            if (e instanceof GroupDoesNotExistException) {
+                throw e;
+            }
             e.printStackTrace();
         }
 
+        if (newGroup.getId() < 0) {
+            return null;
+        }
         return newGroup;
     }
 }

src/test/java/mops/gruppen2/domain/GroupTest.java

@@ -1,5 +1,6 @@
 package mops.gruppen2.domain;
 
+import mops.gruppen2.domain.Exceptions.GroupDoesNotExistException;
 import mops.gruppen2.domain.Exceptions.UserAlreadyExistsException;
 import mops.gruppen2.domain.Exceptions.UserNotFoundException;
 import mops.gruppen2.domain.event.*;
@@ -153,4 +154,17 @@ class GroupTest {
 
         assertThat(group.getDescription()).isEqualTo("Tolle Beschreibung");
     }
+
+    @Test
+    void deleteGroup() throws Exception {
+        CreateGroupEvent createGroupEvent = new CreateGroupEvent(1, 1L, "prof1", "hi", "foo");
+        Group group = new Group();
+        group.applyEvent(createGroupEvent);
+
+        DeleteGroupEvent deleteGroupEvent = new DeleteGroupEvent(44, 1, "loescher78");
+        group.applyEvent(deleteGroupEvent);
+
+        assertThat(group.id).isEqualTo(-1L);
+    }
+
 }

src/test/java/mops/gruppen2/service/GroupServiceTest.java

@@ -0,0 +1,77 @@
+package mops.gruppen2.service;
+
+import mops.gruppen2.domain.Exceptions.GroupDoesNotExistException;
+import mops.gruppen2.domain.Exceptions.UserNotFoundException;
+import mops.gruppen2.domain.Group;
+import mops.gruppen2.domain.event.AddUserEvent;
+import mops.gruppen2.domain.event.CreateGroupEvent;
+import mops.gruppen2.domain.event.DeleteGroupEvent;
+import mops.gruppen2.domain.event.Event;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.*;
+
+class GroupServiceTest {
+    GroupService groupService = new GroupService();
+
+    @BeforeEach
+    public void setUp() {
+    }
+
+    @Test
+    void applyEventOnGroupThatIsDeleted() throws Exception {
+        List<Event> eventList = new ArrayList<>();
+
+        eventList.add(new CreateGroupEvent(1, 10L, "prof1", "hi", "foo"));
+
+        eventList.add(new DeleteGroupEvent(44, 10, "loescher78"));
+
+        eventList.add(new AddUserEvent(900L, 10L, "Ulli", "Ulli", "Honnis", "FC@B.de"));
+
+
+        Assertions.assertThrows(GroupDoesNotExistException.class, () -> {
+            groupService.buildGroupFromEvents(eventList);
+        });
+    }
+
+    @Test
+    void returnDeletedGroup() throws Exception {
+        List<Event> eventList = new ArrayList<>();
+
+        eventList.add(new CreateGroupEvent(1, 10L, "prof1", "hi", "foo"));
+
+        eventList.add(new DeleteGroupEvent(44, 10, "loescher78"));
+
+        assertThat(groupService.buildGroupFromEvents(eventList)).isEqualTo(null);
+    }
+
+    @Test
+    void firstEventNotCreateGroup() throws Exception {
+        List<Event> eventList = new ArrayList<>();
+
+        eventList.add(new DeleteGroupEvent(44, 10, "loescher78"));
+        eventList.add(new CreateGroupEvent(1, 10L, "prof1", "hi", "foo"));
+
+        Assertions.assertThrows(GroupDoesNotExistException.class, () -> {
+            groupService.buildGroupFromEvents(eventList);
+        });
+    }
+
+    @Test
+    void sucsessfullReturnGroup() throws Exception {
+        List<Event> eventList = new ArrayList<>();
+
+        eventList.add(new CreateGroupEvent(1, 10L, "prof1", "hi", "foo"));
+
+        eventList.add(new AddUserEvent(900L, 10L, "Ulli", "Ulli", "Honnis", "FC@B.de"));
+
+        assertThat(groupService.buildGroupFromEvents(eventList)).isInstanceOf(Group.class);
+    }
+
+}